1. (a) Field of the Invention
The present invention relates to a dead bolt assembly, and more particularly to a dead bolt assembly for a tubular door lock.
2. (b) Description of the Prior Art
Various kinds of tubular door locks have been developed and widely used, some of which are disclosed in the following U.S. Patents: U.S. Pat. No. 4,804,216 to Marotto, filed Feb. 1, 1988, entitled "CONVERTIBLE BACKSET LATCH MECHANISM"; U.S. Pat. No. 4,890,871 to Lin, filed Nov. 17, 1988, entitled "TUBULAR DOOR LOCK WITH AN ADJUSTABLE DEVICE FOR SETTING THE DEAD BOLT"; Re. 34,240 of U.S. Pat. No. 4,890,871, to Lin, filed Apr. 17, 1991. U.S. Pat. No. 5,102,175 to Wu et al., filed Nov. 17, 1988, entitled "DEADBOLT ASSEMBLY FOR CYLINDER LOCK"; and U.S. Pat. No. 5,257,838 to Lin, filed Nov. 24, 1992, entitled "DEAD BOLT ASSEMBLY FOR TUBULAR DOOR LOCKS". In these patents, a number of complicated retaining means are provided for retaining the actuating wheel in place.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional tubular door locks.